Electrical contact



July 31, 1934. A. M. DRAVING 1,968,480

l ELECTRICAL CONTACT Filed March 25, 1931 Patented July 31, 1934 PATENTv OFFICE 1.968.480 ELECTRICAL ooN'rAo'r Arthur M. Draving, Philadelphia, Pa., assigner to Hugh H. Eby, Philadelphia, Pa.

Application March 23, 1931, Serial No. 524,435

2 Claims.V

My invention relates to electrical sockets and more particularly to spring contact terminals for receiving the prong terminals of a vacuum tube, loud speaker plug or the like.

In accordance with my invention, a punched yi-shaped spring member is provided with laterally oil'set portions from the parallel. sides thereof adapted to iirmly grip the prongs hroughout a considerable length and give an 1U mproved electrical and mechanical contact.

Further in accordance with my invention the upper ends of the U-shaped member are provided with angular extensions which cooperate mutually and with the socket member in a novel manner.

Still further in accordance with my invention, a plate-like `socket member composed of one or more lamin of insulation material has combined therewith contact terminals of elongated structure extending downwardly from the planeoi.'

said plate-like socket member.

Further purposes will appear in the specification and in the claims.

I have elected to show one main form only of my invention, showing however a minor modication and selecting a form that is practical and eflicient in operationand which well illustrates the principles involved.

Figure 1 is a top plan view of a socket for use 3with the prong terminals of a vacuum tube or the like and having contact members that embody my invention.

Figure 2 isfa section taken upon the line 2-2 of Figure 1.

Figure 3 is a section generally similar to Figure 2 but showing a somewhat different form.

Figure 4 is an enlarged side elevation o1' one of the contact members shown in Figure 2.

Figure 5 is a fragmentary top plan view of Figure 4 andFigure 6 is an inverted perspective view of the structure shown in Figures 4 and 5.

Figure 7 isV a fragmentary top plan View showing a somewhat different form that has in practice proved particularly satisfactory.

Figure 8 is a section taken upon the line 8-8 of Figure 7.

Figure 9 is a broken perspective view of the contact member of Figure 7.

Like numerals refer to like parts in all figures.

Describing in illustration and not in limitation and referring to the drawing:-

My invention is directed to providing an inexpensive and effective contact member that can be confined in small space and still give a snappy 55 spring action. While it is applicable to different (ci. 11a-32s) pin terminals, I have illustrated it embodied in a multiple socket for a radio tube.

Each connector 10 includes contact elements 11 and 12 that extend laterally from the dat side portions 13V and 14 of a U member, preferably 60 from an intermediate portion of the sides of the U, the contact elements and the U together comprising the integral punched metal connector 10.

The opposing contact elements 11 and 12 are thus maintained by their supporting U portions 13 and 14 and are normally spaced from one another a distance somewhat less than the diameter of the pin terminal with. which they are to operate.

'I'he contact surfaces are concaved at l5 par- 70 allel to the'lengths of the U branches to register with the convex surface of the pin terminal which is preferably inserted for somewhat more than the full' length of the contact elements and during insertion pushes the elements apart by a slight 7 5 twisting strain upon the sides of the U.

'Ihe connectors are provided with tail extensions 16 and 17 at the outer ends of the U branches.

'Ihese extensions are bent initially at right 88 i angles to the branches carrying the contact elements and are used for supportingl the connector and also for providing a` terminal for easy connection to an electric circuit.

The tail ends may be bent in opposite directions from the branches of the U as indicated in Figure 2 or may be bent in. the same direction as indicated at 17 in Figure 3. In that case one tail end then passes across the Vintermediate space between the U branches to overlap the other tail.

Obviously the tail bends may be widely variant inform to best suit the many dierent kinds of mounts with which they may be used, the mounts usually comprising single socket or multiple socket receptacles.

In the embodiment ,shown in Figures 1 and 2, the metal strip U members are mounted in registry with the pin terminals of a radio tube, the tail portions 16 and 17 of the connectors being clamped between perforated insulation plates 18 100 The outer tail portions 16 of the connectors extend downwardly through perforations 23 in the lower plate and afford easy connection to the respective electric circuits of thetube, not shown.

Desirably the inner ends 24 of the right bends 17 are bent upwardly into suitable holes in the upper plate 18 in order to more denitely register the branches of the U so that the right angle bends 16' and 17' of each connector overlap one another adjacent the outer leg 12 of the U and I have held each composite connector in place upon the insulation plate 19 by a single tubular rivet 28. One of the right angle bends is extended and bent downwardly at 29 to provide connection into the radio circuit.

As in the Figures 1 and 2, I provide the top of the plate with a raised boss 21' for guiding the prongs of the tube into their sockets.

The ends of the contact elements preferably flare away from one another at one end to perinit more easy entry and-aligning of the prong terminal and at the other end to insure easy withdrawal of the terminal in the event that the end of the terminal should have one or more raised portions, which in practice has not infrequently been the case with the terminals of some commercial vacuum tubes.

The embodiment shown in Figures 7 and 8 has in practice proven very convenient and desirable and to some extent combines desirable features of the other forms.

-The outer leg 13' of the U is provided with an outward right bend underneath the plate 1,92 where it is fastened in place by a suitable rivet 28'.

The inner leg 14' is not attached directly to the plate 192, but the contact element l2' has an inwardly oiset vertical portion 31 that seats at the inner edge of an inward notch 32 in the plate- 192 and has an end 33 bent horizontally inward so as to be between the top of the plate 192 and the bottom of the guiding boss 21.

The notches 32 extend inwardly from the inner sides of the perforations 20 for admitting the pin terminals of the radio socket to the contact members. The perforations 20 are placed so as to adapt the outside circumference of the boss to use as a guide for securing easy entry of the pins into the perforations through the plate to the contact members.

'I'he notch 32 thus extends inwardly from the outer circumference of the boss 212 so that the vertical offset portion 31 is wholly underneath the guide member.

It will be seen that the U is thus supported separately and securely upon inner and outer sides of the perforations 20', and that the mount includes only two or the tlber sheet members.

The terminal portion of the outer leg I3' is widened at 34 in order to provide adequate metal around the rivet 28 that fastens the leg to the plate 192, and is desirably perforated at 35 for more convenient connection to a terminal conducclsor of the circuit with which the member is use i As will be seen the otherwise free ends of the U are ysecured by engagement with the support to which the contact device is attached and the outer ends of the U are supported by cross connection to one another at the bridge of the U. 'Ihis greatly stiiens the sides so that for the same strength they can be made of narrower or thinner material than would otherwise be required. At the same time it permits very compactv construction to secure the strength that is required, and in particular, gives good side support to the contact pieces by which the pin is engaged. The result is that a torsional action is obtained, the contact members 11 and 12 bending about the sides 13 and 14 respectively of the U as axes. This prevents spreading of the U or a permanent set in the region of l0.

In view of my invention and disclosure variations and modifications to meet individual preference or particular need will doubtless become evident to others skilled in the art, to obtain all or part oi' the beneiits of my invention without copying the structure shown, and I, therefore, claim all such in so far as they fall within the reasonable spirit and scope o1' my invention.

Having thus described my invention, what I claiml as new and desire to secure by Letters Patent is:

1. A contact clip of spring metal comprising a U-shaped member, contact pieces extendinglaterally from the arms of the U and internally concaved to iit the pin of a contact member along a considerable portion of the length of the pin and terminala for attachment purposes supporting respectively the two sides of the U one of the ends ofthe U being extended for electrical connection to the contactclip, the said pin terminal to be inserted generally parallel tothe arms of the U and the said contact pieces making integral connections with the arms along a major portion of the length of one side of the said pieces and e having free edges along their sides opposite the lines oi connections with the said arms.

2. A spring metal contact member comprising a U strip adapted to be supported at the othervwise free ends of the U., the ends of the U being bent at right angles for attachment purposes and one end of the U being extended to serve as an electrical connection to the contact, and parallel,`

lateral extensions from the two arms of the U inwardly concave longitudinally of the branches of the U and spaced to engage a contact pin' side of the extensions and having free edges along the sides of the extension opposite the lines of connection with the said arms.

ARTHUR M. DRAVING. 

